The State of Colorado is shaped like a rectangle. The borders are latitude and longitude lines. The four borders are at 37°N, 41°N, 102°03'W, and 109°03'W. (The east and west borders are 25°W and 32°W from the Washington Meridian.) Colorado, Wyoming, and Utah are the only three U.S. states that have only lines of latitude and longitude for boundaries and that have no natural borders. When government surveyors made the border markers for the "Territory of Colorado", minor surveying mistakes made many small kinks along the borders, most seen along the border with the "Territory of Utah."

The weather and temperatures in Colorado are quite different compared to most of the United States. In most other states, the part in the south is warmer than the part in the north, southern Colorado is not really warmer than northern Colorado. Mountains and surrounding valleys greatly affectlocal climate. As a normal rule, with an increase in height comes a decrease in temperature and an increase in rain. There exists a phenomenally severe change in climate in Colorado between the Rocky Mountains on the west and the plains on the east, both of which are separated by a lesser range known to Colorado citizens and primarily Boulderites as "the foothills".

The state's largest city, and capital, is Denver. The "Denver-Aurora-Boulder Combined Statistical Area", is home to 2,927,911 people, it has more than two-thirds of the state's population.

As of 2005, Colorado has an estimated population of 4,665,177, which is an increase of 63,356, or 1.4%, from the last year and an increase of 363,162, or 8.4%, since the year 2000. This has a natural increase since the last census of 205,321 people (that is 353,091 births minus 147,770 deaths) and an increase because of migration of 159,957 people into the state. Immigration from outside the United States makes a net increase of 112,217 people, and migration within the country made a net increase of 47,740 people.

The Bureau of Economic Analysisestimates that the total state product in 2007 was $236 billion. Per capita personal income in 2007 was $41,192, ranking Colorado eleventh in the United States. Early companies were based on the extraction and getting minerals and agricultural things. Today's agricultural things are cattle, wheat, dairy products, corn, and hay. On January 1 2014 Colorado became the first state to make marijuana legal.[3] In the first week of this $5 million of marijuana was sold.[4] The marijuana industry is expected to make Colorado's economy $359 million by the end of 2014.[5]